Transseptal systems and methods

ABSTRACT

A transseptal system includes a needle, a guidewire, a handle, and a dilator. The handle defines a needle passage to slidably receive the needle, and a guidewire passage to slidably receive the guidewire. The dilator defines a lumen having a distal region and a proximal region. The dilator is coupled to the handle such that the lumen is open to the needle passage and the guidewire passage. The proximal region of the lumen is sized to simultaneously receive the needle body and the guidewire. The distal region is sized to slidably receive one of the needle and the guidewire on an individual basis. A transseptal puncture and access procedure can be performed, including puncturing tissue with the needle followed by immediate advancement of the guidewire into the accessed area, eliminating the need for multiple instrument exchanges during the procedure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 17/554,576, filed Dec. 17, 2021, which claimspriority to U.S. Provisional Patent Application No. 63/149,468, filedFeb. 15, 2021, the entire contents of each of which are incorporatedherein by reference.

FIELD

The present disclosure relates to transseptal systems and methods. Moreparticularly, it relates to systems and methods for performing anintracardiac transseptal puncture and access procedures, such as topuncture the atrial septum to gain access to the left atrium.

BACKGROUND

Many cardiac treatment procedures require access to the left atrium ofthe heart. For intravenous access, transseptal puncture is a criticalstep in gaining access to the left side of the heart. Typically, aclinician uses a sheath, dilator, puncturing or transseptal needle, anda guidewire. During a transseptal puncture/access procedure, the dilatoris housed within the sheath, advanced into the superior vena cava (SVC)(or at least higher than the septal access point), then the guidewire isremoved and is replaced by the transseptal needle, keeping care not todamage any atrial or venous structure. The needle, dilator, and sheathare then collectively retracted (which brings the tip of the dilatorfrom the SVC into the right atrium and to the desired access point onthe atrial septum, typically at the fossa ovalis). With the tip of thetransseptal needle within the dilator, the sheath and/or the dilator isslowly and iteratively advanced, pushing against, and creating “tenting”within, the septum. The transseptal needle is then advanced to penetrateor puncture the atrial septum. Subsequently, the dilator and sheath willbe advanced through the so-created puncture opening and into the leftatrium, enlarging the septal opening and providing access to the leftatrium. With some techniques, a guide wire is employed to better ensurethat the dilator safely crosses into the left atrium and/or is safelylocated within the left atrium. For example, after puncturing the atrialseptum, only a small portion of the dilator is advanced into the leftatrium then the transseptal needle is removed, replaced with aguidewire. The guidewire is advanced into the left atrium and optionallyanchored or placed to mitigate inadvertent damage to the cardiac tissuesor structures (e.g., being placed within one of the left pulmonaryveins). The guidewire can thus stabilize forward advancement of both thedilator and the sheath. As a point of reference, in some instances thetip of dilator may “jump” forward and perforate an adjacent structure,such as the left atrial free wall. Using a guidewire to help pass thedilator and sheath across the intra-atrial septum thus makes advancingthe dilator safer.

The transseptal puncture systems and methods described above arewell-accepted. While the use of guidewires is beneficial withtransseptal puncture procedures, various time-consuming device exchangesare typically required.

SUMMARY

The inventors of the present disclosure have recognized a need toaddress one or more of the above-mentioned problems. The details of oneor more aspects of the disclosure are set forth in the accompanyingdrawings and the description below. Other features, objects, andadvantages of the techniques described in this disclosure will beapparent from the description and drawings, and from the claims.

Some aspects of the present disclosure relate to a transseptal system.The transseptal system includes a needle body, a guidewire, a handle,and a dilator body. The needle body defines a distal tip and anintermediate section proximal the distal tip. The guidewire defines aleading end and an intermediate segment proximal the leading end. Thehandle defines a needle passage and a guidewire passage. The needlepassage is sized to slidably receive the intermediate section of theneedle body, and the guidewire passage is sized to slidably receive theintermediate segment of the guidewire. The dilator body defines a distalend, a proximal end, and a lumen having a distal region open to thedistal end and a proximal region open to the proximal end. The proximalend of the dilator body is coupled to the handle such that the lumen isopen to the needle passage and the guidewire passage. The proximalregion of the lumen is sized to simultaneously receive the intermediatesection of the needle body and the intermediate segment of theguidewire. Further, the distal region of the lumen is sized to slidablyreceive the intermediate section of the needle body and the intermediatesegment of the guidewire on an individual basis. With this construction,a transseptal puncture and access procedure can be performed, includingpuncturing tissue with the needle body followed by immediate advancementof the guidewire into the accessed area, eliminating the need formultiple instrument exchanges during the procedure. The distal segmentof the dilator lumen is sized to disallow the advancement of both theguidewire and the needle simultaneously, thereby reducing risk ofinadvertent/unintended puncture or damage. In some embodiments, thehandle is provided as part of a handle assembly further including anactuator device connected to the handle and configured to retain theneedle body. In some related embodiments, the actuator device isslidably connected to the handle. In some related embodiments, thehandle and the actuator mechanism define a complementary engagementarrangement configured to selectively secure the actuator mechanism bodyrelative to the handle in the rearward position. In some relatedembodiments, the handle assembly further includes a safety tab removablyconnected to the handle and arranged to prevent the actuator mechanismfrom being directed to a forward position.

Other aspects of the present disclosure related to a transseptal system.The transseptal system includes a handle assembly, a dilator body, and aneedle body. The handle assembly includes a handle defining a needlepassage and a guidewire passage. The dilator body defines a longitudinalaxis, distal end, a proximal end, and a lumen having a distal regionopen to the distal end and a proximal region open to the proximal end.In this regard, a cross-sectional maximum outer dimension of the distalregion of the lumen in a plane perpendicular to the longitudinal axis isless than a cross-sectional maximum outer dimension of the proximalregion of the lumen in a plane perpendicular to the longitudinal axis.The proximal end of the dilator body is coupled to the handle such thatthe lumen is open to the needle passage and the guidewire passage. Theneedle body is coupled to the handle assembly and slidably receivedwithin the needle passage and the lumen. In some embodiments, the systemfurther includes a guidewire configured to be slidably received withinthe guidewire passage and the lumen. In some embodiments, the needlebody is formed of metal or other electrically conductive material thatcan optionally allow for electrical ablation (e.g., via RF energyapplied by the needle body) to effect, or assisting in effecting, atissue puncture.

Other aspects of the present disclosure relate to a method of creating atransseptal passage. The method includes advancing a dilator body over aguidewire to bring a distal end of the dilator body into contact with afirst side of an atrial septum, the guidewire being slidably receivedwithin a lumen of the dilator body. The guidewire is retracted relativeto the dilator body such that a leading end of the guidewire is locatedwithin the lumen. A hole is formed through the septum with a needle bodywhile the leading end of the guidewire is maintained within lumen. Inthis regard, the needle body is advanced along the lumen to cause adistal tip of the needle body to extend from the distal end of thedilator body and puncture through the first side of the atrial septum toan opposing, second side of the atrial septum. The needle body isretraced relative to the dilator body following the step of forming ahole such that the distal tip of the needle body is located within thelumen. The guidewire is then advanced relative to the dilator body suchthat the leading end of the guidewire extends distally beyond the distalend of the dilator body and the second side of the atrial septum. Insome embodiments, the step of advancing the guidewire includes directingthe leading end into a left atrium.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is simplified, exploded view of a transseptal system inaccordance with principles of the present disclosure;

FIG. 2 is a simplified, longitudinal cross-sectional view of a portionof a dilator body component of the system of FIG. 1 ;

FIG. 3A is a transverse cross-sectional view of the dilator body of FIG.2 , taken along the line 3A-3A;

FIG. 3B is a transverse cross-sectional view of the dilator body of FIG.2 , taken along the line 3B-3B;

FIG. 4A is a transverse cross-sectional view of needle body andguidewire components of the system of FIG. 1 , along with the dilatorbody cross-section of FIG. 2 ;

FIG. 4B is a transverse cross-sectional view representing the needlebody and guidewire disposed within the dilator body;

FIG. 5 is a simplified, longitudinal cross-sectional view of a portionof the system of FIG. 1 , including the dilator body, needle body andguidewire;

FIG. 6 is a side view of a portion of a transseptal system in accordancewith principles of the present disclosure, including a handle assemblyuseful with the system of FIG. 1 ;

FIG. 7 is a longitudinal cross-sectional view of a handle component ofthe handle assembly of FIG. 6 ;

FIG. 8 is the cross-sectional view of the handle of FIG. 7 , along witha portion of the dilator body assembled to the handle;

FIG. 9A is a transverse cross-sectional view of the handle of FIG. 7 ,taken along the line 9A-9A;

FIG. 9B is a transverse cross-sectional view of the handle of FIG. 7 ,taken along the line 9B-9B;

FIG. 10 is a top view of a portion of the system of FIG. 6 ;

FIG. 11 is a longitudinal cross-sectional view of a portion of thesystem of FIG. 10 ;

FIG. 12 is a side view of a portion of the system of FIG. 6 ,illustrating an arrangement of a needle distal tip relative to a dilatorbody distal end in a needle deployment state;

FIG. 13A is a simplified perspective view of a handle assembly usefulwith the system of FIG. 1 , along with a needle body retained by thehandle assembly;

FIG. 13B is an enlarged side view of a portion of the handle assembly ofFIG. 13A;

FIG. 14 is a simplified side view of a handle assembly useful with thesystem of FIG. 1 , along with a needle body retained by the handleassembly; and

FIGS. 15-16C illustrate transseptal puncture and access methods inaccordance with principles of the present disclosure.

DETAILED DESCRIPTION

Specific embodiments of the present disclosure are now described withreference to the figures, wherein like reference numbers indicateidentical or functionally similar elements. The terms “distal” and“proximal” are used in the following description with respect to aposition or direction relative to the treating clinician. “Distal” or“distally” are a position distant from or in a direction away from theclinician. “Proximal” and “proximally” are a position near or in adirection toward the clinician.

It should be understood that various aspects disclosed herein may becombined in different combinations than the combinations specificallypresented in the description and accompanying drawings. It should alsobe understood that, depending on the example, certain acts or events ofany of the processes or methods described herein may be performed in adifferent sequence, may be added, merged, or left out altogether (e.g.,all described acts or events may not be necessary to carry out thetechniques). In addition, while certain aspects of this disclosure aredescribed as being performed by a single module or unit for purposes ofclarity, it should be understood that the techniques of this disclosuremay be performed by a combination of units or modules associated with,for example, a medical device.

Some aspects of the present disclosure provide a transseptal system forperforming an intracardiac transseptal puncture and access procedure.One example of a transseptal system 20 in accordance with principles ofthe present disclosure is shown in simplified form in FIG. 1 , andincludes a needle body 30, a guidewire 32, a dilator body 34 and ahandle 36. Details on the various components are provided below. Ingeneral terms, the dilator body 34 is connected to the handle 36, andterminates at distal end 40. Further, the dilator body 34 forms a lumen(not shown), a proximal region of which is sized to simultaneouslyreceive the needle body 30 and the guidewire 32 via correspondingpassages (not shown) in the handle 36. In a region of the distal end 40,the dilator body lumen is sized and shaped to slidably receive theneedle body 30 or the guidewire 32 on an individual basis. With thisconstruction, a transseptal puncture and access procedure can beperformed, including puncturing tissue with the needle body 30 followedby immediate advancement of the guidewire 32 into the accessed area,eliminating the need for multiple instrument exchanges during theprocedure.

The needle body 30 can assume various forms appropriate for performing atransseptal puncture as is known in the art (e.g., a Brockenbroughneedle or similar tissue puncture device), and can be viewed as havingor defining a proximal section 50, and intermediate section 52, and adistal tip 54. The intermediate section 52 is proximal the distal tip54, and defines at least a majority of an axial length of the needlebody 30. In this regard, the intermediate section 52 has a substantiallyuniform outer diameter (i.e., within 5% of a truly uniform outerdiameter), with the diameter of the needle body 30 tapering to a sharpedpoint along the distal tip 54. The proximal section 50 may or may nothave an enlarged diameter as compared to the intermediate section 52.Further, the proximal section 50 may from or can be connected to anauxiliary component, such as a hub (not shown), for example a hubconfigured to facilitate flushing or pressure monitoring of an optionalinternal lumen of the needle body 30. In some embodiments, the needlebody 30 is formed of metal or other electrically conductive materialthat can optionally allow for electrical ablation (e.g., via RF energyapplied by the needle body) to effect, or assisting in effecting, atissue puncture.

The guidewire 32 can also have any construction known in the artconducive to traversing a patient's vascular system, for example throughthe femoral vein to the superior vena cava (SVC). The guidewire 32 canbe viewed as defining a proximal segment 60, an intermediate segment 62,and a leading segment 64 terminating at a leading end 66. Theintermediate segment 62 defines at least a majority of an axial lengthof the guidewire 32, and has a substantially uniform outer diameter(i.e., within 5% of a truly uniform outer diameter). The leading segment64 can have an outer diameter commensurate with that of the intermediatesegment 60, or may exhibit a reduced outer diameter in extension to theleading end 66. In some embodiments, the leading segment 64 can beconfigured to self-assume a predetermined shape, such as a J-tip as isknown in the art. With these and related embodiments, the leadingsegment 64 can be forced to a straightened shape (e.g., when disposedwithin a lumen of a separate device), and will self-revert to thepredetermined shape when the force is removed (e.g., the guidewire 32can be formed from a shape memory type material). The proximal segment60 may or may not have an enlarged diameter as compared to theintermediate segment 62, and from or be connected to an auxiliarycomponent, such as a handle (not shown).

The dilator body 34 can be, or can be akin to, an elongated sheath ortube, and defines a proximal end 70 opposite the distal end 40. At leasta majority of the dilator body 34 can have a substantially uniform outerdimension or shape in longitudinal extension from the proximal end 70 toa distal zone 74. An outer dimension of the dilator body 34 can taperalong the distal zone 74 to the distal end 40, with the distal zone 74thus serving as an atraumatic surface for expanding a hole or opening intissue when inserted there through as is known in the art. The dilatorbody 34 can be longitudinally straight or can be formed to define acurve along a longitudinal length thereof.

With additional reference to FIG. 2 , the dilator body 34 defines alumen 80 extending between the proximal end 70 and the distal end 40. Asize and/or shape of the lumen 80 varies along a length of the dilatorbody 34, and can include a proximal region 82 and a distal region 84.The proximal region 82 of the lumen 80 is open to the proximal end 70,and the distal region 84 is open to the distal end 40. In general terms,the proximal region 82 of the lumen 80 is sized and/or shaped tosimultaneously receive both the intermediate section 52 of the needlebody 30 and the intermediate segment 62 of the guidewire 32, whereas thedistal region 84 is sized and/or shaped to receive only one of theneedle body 30 and the guidewire 32 on an individual basis.

Geometry features of the lumen 80 in accordance with some embodiments ofthe present disclosure can be described with respect to a longitudinalaxis A defined by the elongated shape of the dilator body 34. Forexample, FIG. 3A is a transverse cross-sectional representation of thedilator body 34 along the proximal region 82 of the lumen 80, taken in aplane perpendicular to the longitudinal axis A; FIG. 3B is a transversecross-sectional representation along the distal region 84, also in aplane perpendicular to the longitudinal axis A. As a point of reference,while FIGS. 3A and 3B illustrate the lumen 80 as having a circular shapein transverse cross-section at both the proximal region 82 and thedistal region 84, other shapes are also acceptable (regular shapes orirregular shapes), and the shape need not be the same or uniform at theproximal and distal regions 82, 84. Regardless, a shape of the lumen 80defines a maximum outer dimension (e.g., a diameter in the non-limitingexamples of FIGS. 3A and 3B). For example, the lumen 80 has a maximumouter dimension OD_(P) along the proximal region 82 (again, intransverse cross-section), and a maximum outer dimension OD_(D) alongthe distal region 84. The transverse cross-sectional maximum outerdimension OD_(P) of the lumen 80 along the proximal region 82 is greaterthan the transverse cross-sectional maximum outer dimension OD_(D) alongthe distal region 84. In some embodiments, a transverse cross-sectionalarea of the lumen 80 along the proximal region 82 is greater than atransverse cross-section area along the distal region 84. Withadditional reference to FIG. 2 , a transition region 86 can beestablished between the proximal region 82 and the distal region 84along with the lumen 80 tapers in outer dimension. Regardless, alongitudinal length of the distal region 84 is less than a longitudinallength of the proximal region 82, for example at least 75% less is someembodiments. In other embodiments, a longitudinal length of the distalregion 84 (i.e., longitudinal distance from the distal end 40 to thetransition region 86) can be on the order of 0.5-10 centimeters,alternatively not more than 5 centimeters. In some embodiments, thedistal region 84 of the lumen 80 can generally correspond with alocation of the distal zone 74.

As indicated above, a size and/or shape of the lumen 80 along each ofthe proximal and distal regions 82, 84 is selected in accordance withtraverse cross-sectional geometry features of the needle body 30 and theguidewire 32. For example, FIG. 4A illustrates the transversecross-sectional representation of the dilator body 34 along the proximalregion 82 (as in FIG. 3A), along with side-by-side, transversecross-sectional representations of the needle body 30 (along theintermediate section 52) and the guidewire 32 (along the intermediatesegment 62). While the needle body intermediate section 52 and theguidewire intermediate segment 62 may or may not have the circulartransverse cross-sectional shape implicated by FIG. 4A. Further, atransverse cross-sectional area of the needle body intermediate section52 may or may not be less than a transverse cross-section area of theguidewire intermediate segment 62 as otherwise implicated by FIG. 4A.Regardless, when arranged side-by-side, the needle body intermediatesection 52 and the guidewire intermediate segment 62 combine to define amaximum combined working dimension WD in transverse cross-section. Withthis in mind, the transverse cross-sectional maximum outer dimensionOD_(P) of the lumen 80 along the proximal region 82 is greater than thetransverse cross-sectional maximum combined working dimension WD of theneedle body intermediate section 52 and the guidewire intermediatesegment 62. In other embodiments, a relationship of the proximal region82 with respect to the needle body 30 and the guidewire 32 can bedescribed as the transverse cross-sectional area of the lumen 80 alongthe proximal region 82 is greater than a combined transversecross-sectional area of the needle body intermediate section 52 and theguidewire intermediate segment 62. With this construction, the needlebody 30 (and in particular at least the intermediate section 52 thereof)and the guidewire 32 (and in particular at least the intermediatesegment 62 thereof) can simultaneously reside within the lumen 80 alongthe proximal region 82 as reflected by FIG. 4B.

In contrast, and with reference between FIGS. 3B and 4A, the transversecross-sectional maximum outer dimension OD_(D) of the lumen 80 along thedistal region 84 is less than the transverse cross-sectional maximumcombined working dimension WD of the needle body intermediate section 52and the guidewire intermediate segment 62. In other embodiments, arelationship of the distal region 84 with respect to the needle body 30and the guidewire 32 can be described as the transverse cross-sectionalarea of the lumen 80 along the distal region 84 is less than a combinedtransverse cross-sectional area of the needle body intermediate section52 and the guidewire intermediate segment 62. With this construction,the needle body intermediate section 52 and the guidewire intermediatesegment 62 cannot simultaneously reside within the lumen 80 along thedistal region 84 in some embodiments. However, the transversecross-sectional maximum outer dimension OD_(D) of the lumen 80 along thedistal region 84 is at least slightly greater than the transversecross-sectional maximum outer dimension of the needle body intermediatesection 52, and is at least slightly greater than the transversecross-sectional maximum outer dimension of the guidewire intermediatesegment 62. In other embodiments, the transverse cross-sectional area ofthe lumen 80 along the distal region 84 is greater than the transversecross-sectional area of the needle body intermediate section 52, and isgreater than the transverse cross-sectional area of the guidewireintermediate segment 62. Thus, the needle body intermediate section 52or the guidewire intermediate segment 62 can each be slidably receivedon an individual basis within the lumen 80 along the distal region 84,but not simultaneously.

Geometry features of the dilator body lumen 80 relative to the needlebody 30 and the guidewire 32 can further be described with reference toFIG. 5 . In the arrangement of FIG. 5 , the needle body 30 and theguidewire 32 have been loaded into the lumen 80, and simultaneouslyreside along the proximal region 82. The needle body 30 is arranged suchthat the distal tip 54 is within the proximal region 82 of the lumen 80(i.e., is proximal the distal end 40 of the dilator body 34), whereasthe guidewire 32 has been distally advanced relative to the needle body30 and the dilator body 34, including the intermediate segment 62extending along and through the distal region 84 of the lumen 80, andthe leading end 66 located distal the distal end 40 of the dilator body34. As a point of reference, FIG. 5 further reflects an optionalconstruction of the guidewire 32 in which the leading segment 64self-reverts to a J-like shape when released from the confines of thelumen 80. Regardless, with the arrangement of FIG. 5 , the distallyexposed portion of the guidewire 32 can be utilized in performing one ormore steps of an intended procedure, while the needle body 30 remains“covered” by the dilator body 34. In some embodiments, then, FIG. 5represents a first deployment state of the transseptal system 10. When aparticular procedure calls for deployment of the needle body 30, theguidewire 32 can be proximally retracted relative to the dilator body34, bringing the leading end 66 into the proximal region 82 of the lumen80 such that the guidewire 32 no longer occupies the distal region 84;the needle body 30 can then be distally advanced relative to the dilatorbody 34, directing the distal tip 54 into and through the distal region84 of the lumen 80. In this second deployment state of the transseptalsystem 10, the distal tip 54 of the needle body 30 can be utilized for adesired procedural step (e.g., to pierce or puncture tissue), while theguidewire 32 remains “covered” by the dilator body 34. As desired, theneedle body 30 can later be proximally retracted, followed by distaladvancement of the guidewire 32. This instrument exchange (e.g.,replacing the guidewire 32 with the needle body 30 distal the distal end40 of the dilator body 34, or vice-versa) can be performed quickly, anddoes not necessitate complete removal of the needle body 30 or theguidewire 32 from the dilator body 34. Further, the needle body lumen 80serves as a central lumen that is flushable.

Returning to FIG. 1 , the handle 36 can assume various forms conduciveto loading and manipulating the needle body 30 and the guidewire 32relative to the dilator body 34. In some embodiments, the proximal end70 of the dilator body 34 can be attached (e.g., permanently attachedsuch as be adhesive, welding, etc.) to the handle 36. In otherembodiments, the dilator body 34 can be selectively mounted to thehandle 36 by an end user. Further, the handle 36 can optionally beprovided as part of a handle assembly having additional, optionalfeatures. With this in mind, one non-limiting example of a handleassembly 100 in accordance with principles of the present disclosure isshown in FIG. 6 . The handle assembly 100 includes a handle 102, anoptional actuator device 104 (referenced generally), an optional grip106, and an optional connector hub 108. As a point of reference, in theview of FIG. 6 , the dilator body 34 is fixed to the handle 102, and theneedle body 30 and the guidewire 32 have been loaded to the handle 102.Where provided, the optional connector hub 108 is carried by the handle102 and can have a conventional design appropriate for receiving theguidewire 32 (e.g., a Luer Lock-type connector hub).

In some embodiments, the handle 102 and the grip 106 can be integrallyor homogenously formed, with the grip 106 generally configured tofacilitate grasping of the handle assembly 100 by a single hand of auser. In some optional embodiments in which the dilator body 34 forms ordefines a curve along a longitudinal length thereof, a shape or otherfeature of the grip 106 can be configured to indicate to a user ageneral direction of the curvature relative to the handle 102 (e.g., anindication as to which way the dilator body 34 is “pointing”).Alternatively or in addition, other features can be provided that denoteorientation (e.g., a marking can be provided on the handle 102 to theeffect of “curved dilator” or the like, indicating to a user which waythe dilator body 34 is curved). Regardless, the grip 106 can assumevarious shapes and sizes that may or may not be implicated by the viewof FIG. 6 . In other embodiments, the grip 106 can be omitted.Regardless, and with reference to FIG. 7 , the handle 102 defines, insome embodiments, a needle passage 120 and a guidewire passage 122. Theneedle passage 120 is sized to slidably receive at least theintermediate section 52 of the needle body 30 (FIG. 1 ), whereas theguidewire passage 122 is sized to slidably receive at least theintermediate segment 62 of the guidewire 32 (FIG. 1 ). Further, theneedle passage 120 and the guidewire passage 122 are both open to a port124 otherwise configured for connection to the dilator body 34 (FIG. 1). In particular, and as best shown in FIG. 8 , upon assembly of theproximal end 70 of the dilator body 34 to the port 124, the lumen 80 isopen to the needle passage 120 and the guidewire passage 122. Thus, theneedle body 30 can extend through the needle passage 120 and the lumen80, and the guidewire 32 can extend through the guidewire passage 122and the lumen 80. As a point of reference, FIG. 8 generally reflects onenon-limiting example of a connection between the dilator body 34 and thehandle 102 in accordance with principles of the present disclosure inwhich the proximal end 70 is inserted into the port 124. In otherembodiments, the proximal end 70 can be inserted over the port 124. Withthese and other techniques, the dilator body 34 can optionally bepermanently affixed to the handle 102 (e.g., adhesive, welding, etc.).In other embodiments, a releasable connection can be established. In yetother embodiments, one or more additional structures or components canbe provided that facilitate connection between the dilator body 34 andthe handle 102. Regardless, upon final assembly, the dilator body lumen80 is open to the needle passage 120 and the guidewire passage 122. Inother embodiments of the present disclosure, the handle 102 forms asingle passage open to the dilator body lumen 80 and sized tosimultaneously receive both the needle body 30 and the guidewire 32.

The handle 102 is shown in an upright orientation in the views of FIGS.7 and 8 , reflecting an orientation when handled by a user. Relative tothis upright or “in use” orientation, the needle passage 120 can bearranged generally vertically above the guidewire passage 122 in someembodiments. Further, the passages 120, 122 can be arranged such that adistal side 126 of the needle passage 120 intersects the guidewirepassage 122. In some embodiments, at least at the point of intersectionof the needle passage 120 with the guidewire passage 122, a longitudinalcenterline of the needle passage 120 is off-set from that of theguidewire passage 122. For example, the cross-section of FIG. 9Aillustrates the needle passage 120 having or defining a longitudinalcenterline CN and the guidewire passage 122 having or defining alongitudinal centerline CG. In the cross-sectional plane of FIG. 9A,while the needle passage 120 and the guidewire passage 122 are separateor distinct from one another, the needle passage centerline CN can behorizontally off-set (e.g., in the x-direction) from the guidewirepassage centerline CP. In the cross-sectional plane of FIG. 9B, theneedle passage 120 is now open to the guidewire passage 122. At thispoint of intersection, the needle passage centerline CN is off-set bothhorizontally and vertically relative to the relative to the guidewirepassage centerline CG. With these and other off-set arrangements, aneedle body extending through the needle passage 120 and into theguidewire passage 122 is less likely to interfere with a guidewireextending through the guidewire passage 122.

Returning to FIGS. 6 and 8 , the handle assembly 100 can be configuredto interface with the needle body 34 in various manners conducive toslidably maintaining the needle body 34 relative to the needle passage120, and thus relative to the dilator body lumen 80. In someembodiments, the needle body 30 can be selectively assembled to andremoved entirely from the handle assembly 100. In other embodiments, thehandle assembly 100 is configured to retain the needle body 30 via theactuator device 104. For example, FIG. 10 is a top view of the handleassembly 100 with the needle body 30 and the dilator body 34 mountedthereto; FIG. 11 is a simplified cross-sectional view of the arrangementof FIG. 10 . In some embodiments, the actuator device 104 is slidablyconnected to the handle 102, and includes a pusher body or head 130 anda neck 132. The neck 132 extends from the pusher body 130, and inconfigured to be affixed to the needle body 30 (e.g., adhesive, weld,etc.). The handle 102 defines a slot 134; the neck 132 is sized andshaped to be slidably received within the slot 134. In this regard, awidth of the pusher body 130 is greater than that of the neck 132 andthe slot 134 such that the pusher body 130 is slidable along an exteriorof the handle 102. With this construction, then, the needle body 30 isslidably retained relative to the handle 102 (and thus relative to thedilator body 34) by the actuator device 104. In response to auser-applied force on the pusher body 130, the actuator device 104, andthus the needle body 30 attached thereto, can be manipulated relative tothe handle 102 between a rearward position reflected in FIG. 10 and aforward position generally indicated at 140 in FIG. 10 . A length of theneedle body 30 between the point of attachment with the neck 132 and thedistal tip 54 (FIG. 1 ) corresponds with a distance or length from thedilator body distal end 40 (FIG. 1 ) and the forward and rearwardpositions. In particular, when the actuator device 104 is in therearward position, the needle body distal tip 54 is disposed within theproximal region 82 of the dilator body lumen 80 (e.g., the arrangementof the needle body distal tip 54 relative to the dilator body lumen 80shown in FIG. 5 ). When the actuator device 104 is manipulated from therearward position to the forward position 140, the needle body 34 iscaused to slide distally relative to the dilator body 34, locating theneedle body distal tip 54 distal the distal end 40 of the dilator body34. In some embodiments, the handle assembly 100 is configured such thatthe pusher body 130 cannot be forced distally “beyond” the forwardposition 140 (e.g., a structure of the handle 102 serves as a hard stopto distal movement of the neck 132 beyond the distal end of the slot 134that otherwise serves as the designated forward position); with theseand related embodiments, the actuator device provides a pre-definedmaximum distal extension of the needle body distal tip 54 relative tothe dilator body distal end 40 such that the needle body distal tip 54is not inadvertently caused to overly protrude relative to the dilatorbody distal end 40. FIG. 12 illustrates a relationship of the needlebody distal tip 54 relative to the dilator body distal end 40 with theactuator device 104 (FIG. 11 ) in the forward position.

Returning to FIG. 6 , the handle assembly 100 can incorporate or includeone or more other components that facilitate a robust, slidableconnection between the needle body 30 and the handle 102 that may or maynot be implicated by the actuator device 104 as described above. In someembodiments, the handle assembly 100 can include or incorporate featuresthat provide a user with visual and/or tactile cues as to a relationshipof the needle body distal tip 54 relative to the dilator body distal end40. For example, FIGS. 13A and 13B illustrate portions of an alternativehandle assembly 150 in accordance with principles of the presentdisclosure and maintaining the needle body 30. The handle assembly 150can be highly akin to the handle assembly 100 (FIG. 6 ), and includes ahandle 102′ and an actuator mechanism 104′. The handle 102′ forms theslot 134 as described above and along which the actuator mechanism 104′is slidably retained. In this regard, the actuator mechanism 104′ iscoupled to the needle body 30 as described above, and includes a pusherbody 130′. Commensurate with the descriptions above, the pusher body130′ is arranged to receive a user-applied actuation force, causing thepusher body 130′ (and thus the needle body 30) to slide between arearward position as shown, and a forward position (identified generallyin FIG. 13A at 152). The handle 102′ forms a protrusion or bump 160proximate the slot 134 in a region corresponding to the rearwardposition, and the pusher body 130′ forms a complementary groove orindent 162 sized to receive the bump 160. More particularly, the bump160 and the indent 162 are configured and arranged such that when thepusher body 130′ is in the rearward position, the bump 160 is capturedwithin the indent 162, serving as a temporary “lock” of the actuatormechanism 104′ (and thus of the needle body 30) relative to the handle102′. It will be recalled that in the rearward position, the needle bodydistal tip 54 is disposed within the proximal region 82 of the dilatorbody lumen (e.g., the arrangement of the needle body distal tip 54relative to the dilator body lumen shown in FIG. 5 ). Thus, the “lock”generated by an interface between the bump 160 and the indent 162provides feedback to a user that the needle body distal tip 54 is “outof the way” or not otherwise exposed distal the dilator body 34.Further, the locked relationship between the bump 160 and the indent 162resists accidental/unintentional movement of the actuator mechanism 104′relative to the handle 102′, and thus of the needle body 30 relative tothe dilator body 34. Instead, a user must make a concerted effort/applya substantive pushing force onto the pusher body 130′ in order to movethe needle body 30 relative to the dilator body 34. Other complementaryengagement arrangements configurations can be employed (e.g., the bump160 can be carried by the pusher body 130′) appropriate for providing atemporary lock; in yet other embodiments, the temporary locking featurescan be omitted.

Another optional feature that can be provided with some transseptalsystems of the present disclosure is shown in FIG. 14 . In particular,FIG. 14 illustrates, in simplified form, another transseptal system 180in accordance with principles of the present disclosure that includesthe needle body 30 and the dilator body 34 as described above, alongwith a handle assembly 100′. The handle assembly 100′ can be highly akinto the handle assembly 100 (FIG. 6 ), and includes the handle 102, theactuator mechanism 104, and the optional guidewire connector hub 108.The handle assembly 100′ further includes a safety tab 190 removablyconnected to the handle 102 (e.g., the safety tab 190 can have a “snapoff” configuration whereby a user-applied force removes the safety tab190 from the handle 102). As a point of reference, the arrangement ofFIG. 14 represents one example of the system 180 as initially providedto a user. In this initial state, the actuator mechanism 104 secures theneedle body 30 relative to the handle 102 (and thus relative to thedilator body 34), and is located in the rearward position. It will berecalled that in the rearward position, the needle body distal tip 54 isdisposed within the needle body lumen 80 (i.e., the arrangement of FIG.5 ). With this in mind, the safety tab 190 is configured and locatedalong the handle 102 so as to inhibit forward or distal movement of thepusher body 130, thereby inhibiting unintentional or accidental forwardor distal movement of the needle body distal tip 54 distally beyond thedilator body distal end 40. When deployment or extension of the needlebody 30 is desired, the safety tab 190 is removed from the handle 102 bythe user. Once removed, the pusher body 130 can then be freelymanipulated by the user, for example to deploy or extend the needle body30 from the dilator body 34.

The transseptal systems of the present disclosure can be useful inperforming a variety of procedures requiring transseptal puncture andaccess. For example, any procedure that requires access to the leftatrium via the interatrial septum, such as left ventricle endo pacing,left sided ablation, left atrial appendage closure, mitral valverepair/replacement, atrial septostomy, etc. Features of the presentdisclosure can be incorporated into any dilator designed to cross theseptum. By way of non-limiting example, and with initial reference toFIG. 15 , some methods of the present disclosure can include navigatingthe dilator body 34 to a patient's heart through the patient'svasculature, such as by femoral, radial, or brachial access. As a pointof reference, some procedures requiring left atrial access necessitatethe use of a delivery sheath 200 to deliver devices to their intendedlocation within the left side of the heart or associated anatomies. Thetransseptal systems and methods of the present disclosure can beutilized in conjunction with such a delivery sheath to aid in navigationto atrial septal access point. The systems and methods of the presentdisclosure are in no way limited to use with a delivery sheath, and caninclude navigating the dilator body 34 with or without the deliverysheath 200. With this in mind, in the non-limiting example of FIG. 15 ,the delivery sheath 200 may be navigated from the femoral vein, throughthe inferior vena cava, and into the right atrium. With othertechniques, the dilator body 34 is navigated into the right atrium viathe radial, brachial, and superior vena cava. As reflected by FIG. 15 ,the guidewire 32 can be utilized to assist in locating the dilator body34 and/or the optional delivery sheath 200 in the right atrium. It willbe understood that at the procedural stage of FIG. 15 , the needle body30 is within the dilator body lumen 80 as the dilator body 34 isadvanced to the right atrium (e.g., the arrangement of FIG. 5 ). Fromthe right atrium, the transseptal systems of the present disclosure canbe used to puncture the atrial septum, such as through the area ofseptal tissue known as the fossa ovalis, to gain access into the leftatrium.

With reference to FIG. 16A, with the distal end 40 of the dilator body34 proximate a first side 202 of the atrial septum, the guidewire 32 isretracted into the dilator body lumen (i.e., the leading end 66 of theguidewire 32 is proximal the distal end 40 of the dilator body 34). As apoint of reference, the optional delivery sheath 200 (FIG. 15 ) isomitted from the views of FIGS. 16A-16C for ease of understanding. Wherethe delivery sheath 200 is employed, the distal end 40 of the dilatorbody 34 can be distal a distal end of the delivery sheath 200 at theprocedural stage of FIG. 16A. The dilator body 34 (and the needle body30 contained therein) along with the optional delivery sheath 200 aremanipulated (e.g., moved proximally and distally) until a desiredlocation along the septum (e.g., the fossa ovalis) is located, forexample using conventional techniques (e.g., ultrasound, fluoroscopy,etc.). The dilator body 34 and/or the delivery sheath 200 are thenmanipulated to push against and “tent” the first side 202 of the septumat the desired location in some embodiments. Regardless, the needle body30 is then distally advanced relative to the dilator body 34, causingthe distal tip 54 to puncture or pierce through a thickness of theseptum as shown in FIG. 16B, creating a hole or access path in theseptum (e.g., extending from the first side 202 to an opposing, secondside 204 of the septum).

The puncture through the septum creates an access path from the rightatrium to the left atrium. In some embodiments, the dilator body 34 andthe needle body 30 are then advanced in tandem though the hole or accesspath in the septum and into the left atrium, with the dilator distalzone 74 enlarging the hole or access path. The needle body 30 is thenretracted relative to the dilator body 34 (bringing the distal tip 54within the dilator body lumen 80), followed by advancement of theguidewire 32 into the left atrium. In other embodiments, afterpuncturing the septum, the needle body 30 is first retracted relative tothe dilator body 34 (bringing the distal tip 54 within the dilator bodylumen 80); the guidewire 32 is then advanced into the left atrium,followed by advancement of the dilator body 34 over the guidewire 32 toenlarge the septal access path or opening with the dilator distal zone74. Regardless, and as shown in FIG. 16C, the guidewire 32 is ultimatelyadvanced distally beyond the second side 204 of the septum and into theleft atrium while the needle body 30 remains within the dilator bodylumen 80. Where desired, the dilator body 34 (and the needle body 30contained therein) can be removed from the patient while the guidewire32 remains in place, available for guiding other instruments to the leftatrium. In yet other embodiments, the optional delivery sheath 200 canbe advanced through the enlarged septal access path and into the leftatrium, followed by removal of dilator body 34 (and the needle body 30contained therein) and optionally the guidewire 32. With these andrelated embodiments, following removal of at least the needle body 30and the dilator body 34, the delivery sheath 200 remains fully acrossthe septum, available for guiding other instruments to the left atrium.

The systems and methods of the present disclosure provide a markedimprovement over previous designs. The needle and guidewire are housedin a central lumen that is flushable. Following a septal puncture, theneedle can be retracted, and the guidewire immediately advanced into theleft atrium. This allows a user to advance a large sheath and dilatoracross the septum with a wire as a guide (sometimes referred to as railsupport). Conventional systems and methods would necessitate that theneedle be fully removed prior to the guidewire being introduced, so thisstep may at times be omitted. The systems and methods of the presentdisclosure can eliminate the need for needle exchanges prior toadvancement of the guidewire. The systems and methods of the presentdisclosure can reduce complications during transseptal procedures, andcan reduce the number of exchanges, which in turn can reduce thelikelihood of possible harm. However, the systems and methods of thepresent disclosure may not dramatically alter the flow or feelassociated with conventional transseptal crossing procedures.

Although the present disclosure has been described with reference topreferred embodiments, workers skilled in the art will recognize thatchanges can be made in form and detail without departing from the spiritand scope of the present disclosure.

What is claimed is:
 1. A transseptal system comprising: a needle bodydefining a distal tip and an intermediate section proximal the distaltip; a guidewire defining a leading end and an intermediate segmentproximal the leading end; a handle defining a needle passage and aguidewire passage, wherein the needle passage is sized to slidablyreceive the intermediate section of the needle body, and further whereinthe guidewire passage is sized to slidably receive the intermediatesegment of the guidewire; and a dilator body defining a distal end, aproximal end, and a lumen having a distal region open to the distal endand a proximal region open to the proximal end, wherein the proximal endof the dilator body is coupled to the handle such that the lumen is opento the needle passage and the guidewire passage, and wherein theproximal region of the lumen is sized to simultaneously receive theintermediate section of the needle body and the intermediate segment ofthe guidewire.
 2. The transseptal system of claim 1, wherein the dilatorbody defines a longitudinal axis, and further wherein a cross-sectionalmaximum outer dimension of the distal region of the lumen in a planeperpendicular to the longitudinal axis is less than a cross-sectionalmaximum outer dimension of the proximal region of the lumen in a planeperpendicular to the longitudinal axis.
 3. The transseptal system ofclaim 1, wherein a diameter of the intermediate section of the needlebody and a diameter of the intermediate segment of the guidewire combineto define a maximum combined working dimension, and further wherein thedilator body defines a longitudinal axis, and even further wherein across-sectional maximum outer dimension of the distal region of thelumen in a plane perpendicular to the longitudinal axis is less than themaximum combined working dimension.
 4. The transseptal system of claim3, wherein a cross-sectional maximum outer dimension of the proximalregion of the lumen is greater than the maximum combined workingdimension.
 5. The transseptal system of claim 1, wherein the transseptalsystem is configured to provide a first deployment state including: theintermediate section of the needle body disposed within the lumen; thedistal tip of the needle body projecting beyond distal end of thedilator body; and the leading end of the guidewire disposed within theproximal region of the lumen.
 6. The transseptal system of claim 5,wherein the transseptal system is configured to provide a seconddeployment state including: the intermediate segment of the guidewiredisposed within the lumen; the leading end of the guidewire projectingbeyond distal end of the dilator body; and the distal tip of the needlebody disposed within the proximal region of the lumen.
 7. Thetransseptal system of claim 1, wherein the needle passage extends from aproximal side to a distal side, the distal side intersecting, and opento, the guidewire passage.
 8. The transseptal system of claim 1, whereinthe handle is provided as part of a handle assembly further including anactuator device connected to the handle and configured to retain theneedle body.
 9. The transseptal system of claim 8, wherein the actuatordevice is slidably connected to the handle.
 10. The transseptal systemof claim 9, wherein the actuator device includes a pusher body and aneck, and further wherein the head extends from the pusher body and isaffixed to the needle body.
 11. The transseptal system of claim 10,wherein the pusher body is slidable relative to the handle between aforward position and a rearward position, and further wherein thetransseptal system is configured such that in the forward position, thedistal tip of the needle body is distal the distal end of the dilatorbody, and in the rearward position, the distal tip of the needle body isdisposed within the proximal region of the lumen.
 12. The transseptalsystem of claim 11, wherein the handle assembly further includes asafety tab removably connected to the handle and arranged to prevent thepusher body from being directed to the forward position.
 13. Atransseptal system comprising: a handle assembly including a handledefining a needle passage and a guidewire passage; and a dilator bodydefining a longitudinal axis, distal end, a proximal end, and a lumenhaving a distal region open to the distal end and a proximal region opento the proximal end, wherein a cross-sectional maximum outer dimensionof the distal region of the lumen in a plane perpendicular to thelongitudinal axis is less than a cross-sectional maximum outer dimensionof the proximal region of the lumen in a plane perpendicular to thelongitudinal axis, and wherein the proximal end of the dilator body iscoupled to the handle such that the lumen is open to the needle passageand the guidewire passage.
 14. The transseptal system of claim 13,further comprising: a needle body coupled to the handle assembly andslidably received within the needle passage and the lumen; and aguidewire configured to be slidably received within the guidewirepassage and the lumen.
 15. A method of creating a transseptal passage,the method comprising: advancing a dilator body over a guidewire tobring a distal end of the dilator body into contact with a first side ofan atrial septum, the guidewire being slidably received within a lumenof the dilator body; retracting the guidewire relative to the dilatorbody such that a leading end of the guidewire is located within thelumen; and forming a hole through the septum with a needle body whilethe leading end of the guidewire is maintained within lumen, includingadvancing the needle body along the lumen to cause a distal tip of theneedle body to extend from the distal end of the dilator body andpuncture through the first side of the atrial septum to an opposing,second side of the atrial septum.
 16. The method of claim 15, whereinduring the step of advancing the dilator body over the guidewire, thedistal tip of the needle body is located within the lumen.
 17. Themethod of claim 15, wherein during the step of retracting the guidewirerelative to the dilator body, the distal tip of the needle body islocated within the lumen.
 18. The method of claim 15, furthercomprising: retracting the needle body relative to the dilator bodyfollowing the step of forming a hole such that the distal tip of theneedle body is located within the lumen; advancing the guidewirerelative to the dilator body such that the leading end of the guidewireextends distally beyond the distal end of the dilator body and thesecond side of the atrial septum; and advancing a distal zone of thedilator body through the hole to dilate the hole following the step ofadvancing the needle body.
 19. The method of claim 18, furthercomprising: withdrawing the dilator body and the needle body from thepatient following the step of advancing the distal zone of the dilatorbody through the puncture hole; wherein during the step of withdrawing,the guidewire remains within the patient and the leading end is locateddistally beyond the second side of the atrial septum.
 20. The method ofclaim 19, further comprising: advancing a treatment device over theguidewire following the step of withdrawing the dilator body and theneedle body.